I'd say definitely Nokie on a JM on most if not all on that LP. The Mosrites didn't come into the scene until The Ventures in Space (at least that's the first time they appear on a cover). There were 5 or 6 albums between Mashed Potatoes and in Space. But that doesn't mean that they didn't record with the Mosrite before the line was officially released in 1963. IMHO, the tones started showing more variation between the songs around the Surfing album.

Nokie has stated he used a Tele ( probably with a Bigsby) on the first Ventures lp. I think he used this on most of the pre-Mosrite stuff. Just my opinion, but he always sounded way too twangy to be a Jazzmaster. I know there's a few promo pics of him with a JM, but I've never seen any early live photos from the time, so it's tough to say for sure.
I did hear that Nokie originally aproached Semie Mosley to have his JM's neck shaved down because he didn't like it. It was then that Mosely gave him the Mosrite prototype as a loaner while the Jazzy neck was being worked on. Anyone else hear this?

Nokie has stated he used a Tele ( probably with a Bigsby) on the first Ventures lp. I think he used this on most of the pre-Mosrite stuff. Just my opinion, but he always sounded way too twangy to be a Jazzmaster. I know there's a few promo pics of him with a JM, but I've never seen any early live photos from the time, so it's tough to say for sure.
I did hear that Nokie originally aproached Semie Mosley to have his JM's neck shaved down because he didn't like it. It was then that Mosely gave him the Mosrite prototype as a loaner while the Jazzy neck was being worked on. Anyone else hear this?

Well according to Walk Don't Run - The Story of the Ventures Nokie ordered a Jazzmaster when some Fender gear was stolen in the early 60s because he needed a guitar with a trem arm. You're right he did use a tele a lot. It's photographed in that book and it doesn't have a bigsby.

Also according to this book it was the Tele he wanted the neck shaved down on and brought to to Semie.

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"as he stepped into the stealthy night air... little did he know the fire escape was not there"